'Healthy' vitamins to avoid if you're ill - The News International

Are you one of the many who has a pot of vitamins by the kettle or in the bathroom that you vow to take every day - but don’t? There may be no need to feel guilty after all.

 

Ten million of us take vitamins regularly - whether for general health or specific conditions. And we spend a whopping £175?million a year on supplements and pills which contain antioxidants that are claimed to help combat disease. But despite all the promises, the pros and cons of vitamins and supplements are still very debatable - and studies show that some can be bad for your health.

 

Just last month U.S. researchers discovered the routine practice of taking calcium and/or vitamin D supplements to protect against bone loss caused by hormonal therapy for prostate cancer could actually be making patients’ conditions worse.

 

You should always speak to your doctor before taking any supplement, says Professor Hilary Powers, head of human nutrition at Sheffield University.‘Some illnesses can alter the way our body uses vitamins and minerals. Added to that, there may be adverse interactions between medications and supplements which might influence the safety of the supplement or action of the drug.’

 

Remember that it’s the vitamin and mineral supplements taken in addition to your daily diet that can cause problems - not the nutrients found in your day-to-day diet. ‘There’s absolutely no need to limit your intake of certain foodstuffs because they may contain a certain vitamin,’ stresses Sylvia Turner, of the British Dietetic Association.

 

Here, experts reveal the supplements that could be detrimental to common conditions or raise your risk of certain illnesses.More than 5,000 men are given hormonal therapy for prostate cancer every year. This works by blocking the production of the male hormone testosterone, which raises the risk of cancer recurring - the problem is it also makes fractures more likely as testosterone is important for bone mass.

 

Calcium is essential for bone health, and is therefore routinely prescribed. But in a recent study, researchers at Wake Forest Baptist Medical Center, North Carolina, took measurements of bone density from 2,399 men before and after hormonal therapy.

 

The study showed that with an extra 500mg to 1,000mg of calcium (the commonly prescribed amount) men lost bone mineral density. ‘High levels of calcium may have some sort of lowering effect on active vitamin D, which your body needs in order to absorb calcium in the first place,’ says Professor Powers. ‘This then counteracts any effect of the calcium on the bones.’

 

Instead, patients should just keep active to maintain bone strength during this period - then after treatment bone density should be gradually restored.

 

One of the medications commonly used to treat some of the 1.8million people affected by psoriasis is retinoids, in tablet or lotion form. They help by regulating the growth of skin cells - in psoriasis the skin replacement process speeds up, causing red, silvery scales to form.

 

However, because retinoids are a derivative of vitamin A, well known for its role in skin maintenance and repair, taking additional vitamin A can lead to toxicity in the body.

 

‘This is because vitamin A is a fat-soluble vitamin, which means it remains in the body - stored in the liver - unlike water soluble vitamins that pass through the body in urine,’ says Sylvia Turner.

 

In excess (above 0.7mg a day for men or the 0.6mg a day recommended to women) it can lead to problems such as conjunctivitis, alopecia and worsening skin problems.

 

If you have a heart condition, avoid high doses of vitamin E, as this has been shown to increase the risk of more heart trouble.

 

A seven-year international study of 10,000 people with heart disease, peripheral artery disease and diabetes at McMaster University in Ontario found that taking a high dose of vitamin E every day (400iu- about 363mg) was linked to a 13per cent higher risk of heart failure and a 21 per cent increased risk of hospitalisation for heart failure.

 

Previous studies suggested that the substance may affect blood clotting or block the beneficial effects of other nutrients.Meanwhile, potassium helps regulate your heartbeat by triggering your heart to squeeze blood through your body.

 

However, taking it in high doses (over and above the 3,500mg recommended a day) could lead to heart palpitations and irregular heartbeats known as arrhythmias. Also known as niacin, vitamin B3 is involved with metabolism and is important in helping to produce energy from foods we eat.